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RE2: serial port forever



Ok, I checked and if I wait it works. But waiting is depends on length of
string. So, how can I decide that DMA finished to flush fifo or not? Or is
it possible to disable DMA on ser0 and ser2?

> -----Original Message-----
> From:	johan.adolfsson@xxxxxxx.com]
> Sent:	Friday, October 05, 2001 22:59
> To:	Szabo, Tamas; dev-etrax@xxxxxxx.com
> Subject:	Re: serial port forever
> 
> The only reason for this behavior I can think of is that
> we don't wait until all data is sent before we close the port.
> This should be fixed a while ago in the serial driver for
> devboard (with Linux 2.0 a.k. elinux) but it might not be fixed
> in the latest devboard_lx (with Linux 2.4) where the driver isn't yet
> updated to the improvements made in elinux (work in progress)
> 
> (Before closing the port we must wait for the DMA to finish,
>  the fifo to be flushed and then wait one "char time" so that the
>  last byte being shifted out really leaves the pin before we close
>  the port)
> 
> /Johan
> 
> ----- Original Message -----
> From: Szabo, Tamas <Tamas.Szabo@xxxxxxx.com>
> To: <dev-etrax@xxxxxxx.com>
> Sent: Friday, October 05, 2001 4:23 PM
> Subject: serial port forever
> 
> 
> > Hello,
> >
> > It seems that I can understand linux or there is a serious problem with
> > serial port (I hope the first). I wrote a few mail about my problem to
> the
> > list but no answer recieved. I would like to use ser0 and ser2. I try to
> > describe my method which is _very_ simple and it works between 2 PC:
> >
> > - On PC I start sermon or minicom
> > - On devboard type: echo -n "blablabla" > /dev/ttyS0
> >
> > Unfortunately this is not work. The problem appears after a few
> characters
> > (the number of characters depend on baudrate at 9600bps ~3-4 chars).
> Usually
> > the last byte(s) does not transmitted. This means somehow the last
> > characters are cutted (even in middle of byte).
> >
> > I use:
> > cris-dist 1.14
> > devboard_lx 2.0.0
> > linux 2.4.5
> >
> > I checked the mail list, but I did not find anybody who report this
> problem,
> > so I think if this problem only appears for me, this is my mistake. But
> I
> > did not modified the sources or anyting else in packages above, and
> compile
> > without errors, then I download image to flash.
> > And the result is not good. If I can not solve this probem, I can not
> > develeop the my application.
> >
> > Can somebody help me? Peaseeeee!
> >
> > Sza2
> >
> >
> >
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